This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The Mass Spectrometry Core Facility is directed by Jackson Lay and Alan Tackett. Jackson Lay, director of the UA-Fayetteville component of the core, has extensive experience in mass spectrometry, and has received a number of FDA awards. Alan Tackett, director of the UAMS component of the core, is highly experienced in the development of new mass spectrometry proteomics techniques. The UAF and UAMS components of the core are complementary, with UAF focusing on high resolution mass spectrometry to solve difficult problems in protein structure, and UAMS focusing on high-throughput proteomics applications. Equipment in the core includes a Bruker Apex Ultra 9.4 T FT/MS, a Thermo LTQXL with Eksigent NanoLC, and numerous other mass spectrometry instruments. Of the total cost of $6.3 million for the mass spectrometry instrumentation, $1.4 million was provided by University matching funds to COBRE Phase II, while the remaining funds were provided by other grants and institutional funds. The University is committing institutional funds to support permanent staff positions for Dr. Rohana Liyanaga and Dr. Jennifer Gidden at UA-Fayettville, and Dr. Sam Mackintosh at the UAMS component of the core, to maintain and operate the instrumentation and develop new methodologies.